hadoop-common-dev mailing list archives

[jira] Commented: (HADOOP-538) Implement a nio's 'direct buffer' based wrapper over zlib to improve performance of java.util.zip.{De|In}flater as a 'custom codec'

Date

Wed, 08 Nov 2006 17:50:58 GMT

[ http://issues.apache.org/jira/browse/HADOOP-538?page=comments#action_12448212 ]
Raghu Angadi commented on HADOOP-538:
-------------------------------------
FYI: If a user creates a lot of such streams, it could be affected by known issue with direct
buffers (see HADOOP-637).
If there was a way in JNI to copy from java array to C array directly, we could avoid direct
buffer allocation in Java and do a malloc() inside C. In fact JNI documentation says GetPrimitiveArrayCritical()
does not always do a copy.
> Implement a nio's 'direct buffer' based wrapper over zlib to improve performance of java.util.zip.{De|In}flater
as a 'custom codec'
> -----------------------------------------------------------------------------------------------------------------------------------
>
> Key: HADOOP-538
> URL: http://issues.apache.org/jira/browse/HADOOP-538
> Project: Hadoop
> Issue Type: Improvement
> Affects Versions: 0.6.1
> Reporter: Arun C Murthy
> Assigned To: Arun C Murthy
> Fix For: 0.9.0
>
> Attachments: HADOOP-538.patch, HADOOP-538_20061005.tgz, HADOOP-538_20061011.tgz,
HADOOP-538_20061026.tgz, HADOOP-538_20061030.tgz, HADOOP-538_20061107.tgz, HADOOP-538_benchmarks.tgz
>
>
> There has been more than one instance where java.util.zip's {De|In}flater classes perform
unreliably, a simple wrapper over zlib-1.2.3 (latest stable) using java.nio.ByteBuffer (i.e.
direct buffers) should go a long way in alleviating these woes.
--
This message is automatically generated by JIRA.
-
If you think it was sent incorrectly contact one of the administrators: http://issues.apache.org/jira/secure/Administrators.jspa
-
For more information on JIRA, see: http://www.atlassian.com/software/jira